The present invention is directed to a fire barrier for use in building construction. In particular, the present invention is directed to a fire barrier material used in conjunction with wall, ceiling or floor expansion joint systems to aide in the substantial reduction of the chimney effect associated with buildings having these types of expansion joints.
Architects and engineers today must take into account the effects not only of seismic movement, but also those movements caused by building sway, settlement, thermal expansion and contraction. Architects know that any building that may be subjected to ground oscillations must be designed to control and accommodate movement caused by resonation within the structure while additionally providing for tower sway, thermal movement and settlement.
Architects and engineers have designed buildings with various expansion joints between the walls, ceilings and floors to take into account the sway, ground motion, settlement, etc. associated with buildings. However, a disadvantage of the use of expansion joints is that they create a chimney effect in the building structure. Because fire is an ever-present danger in association with any building and the chimney effect at unprotected expansion joints may actually advance a spread, it is highly desirable to utilize a fire barrier in conjunction with any expansion joint assembly to provide additional protection to aid in the prevention of the spreading of any fire. Typically, fire barriers are comprised of wire mesh reinforced with a suitable fire retardant material. This mesh reinforced wire is positioned between the joint prior to the application of the expansion joint assembly. The fire barrier is a highly thermal resistant material which protects the joint from the associated chimney effect within the building construction. Other types of joint treatment systems have included insulated metal foil (i.e. aluminum) layers such as those disclosed in the Fire Resistant Directory, pages 718-721 and 821-823. While these fire resistant barrier layers are suitable for reduction in the chimney effect associated with buildings containing expansion joints, they clearly can be improved. For example, these barrier structures are difficult to install and difficult to handle and ship. The present invention is directed to a barrier material which not only has improved fire resistant properties but also can be easily handled and installed.